Locking mechanism



c. i.'MARKsoN LOCKING MECHANISM Filed Dec.

May 26, 1.931.

Lll

A TTORNE Y v INVENTOR ElEmEnEJ-.Mal/'Kam BY Patented May 26, 1931 UNITED STATES PATENT oFElcE cLEMENs ;r. MARKsoN, or PHILADELPHIA, `PENNSYLVANIA LOCKING MECHAN'ISM t Application led December 19, 1929. Serial' No. 415,177.

This invention relates to a locking mechanism, and has particular reference to the locking of a punch and die in their respective retainers, to secure positive relation between the same, when mounted in an ordinary punch press.

The object of the invention is to provide novel and improved punch and die securing mechanism.

A further object of the invention, is to' spectively, by screws which are centered, by

means of dowels, so as to insure the proper relation of the punch and die, recesses adjacent the punch and die, .a slot in the die shank and a slot in the punch shank, and an eccentric plate, located in each recess, and held against vertical movement therein by a bolt, said eccentric plate being adapted tobe turned, on said bolt, to engage the slot in the punch shank or die shank so that, upon the tightening of said bolt the die or punch will be securely held in the respective retainers.

The drawings illustrate an embodiment of the invention and the views therein are as follows:

Figure l is a fragmentary view, showing the relation between the punch and the die of an ordinary punchpress,

Figure 2 is a cross-sectional viewV taken on the line 2-2 of Figure 1 and looking upward in the direction of the arrows, and

Figure 3 is a like view taken on the line" 3 3 of Figure 1 and looking downward in the direction of the arrows.

In the ordinary punch press, afterthe machine has been operating for a period of time, it often happens that the punch and die get out of their proper relative positions, which VThe particular manner of securingwthe punch tools, shownand described in this application, is intendedto eliminate these obv.. )ecti'onsand to permit both the punch and the die to be quickly secured in theirrespective retainers, without :the removal of any parts, and in vsuch a manner that when boththe die or tool are so 'held'the estab- .g lished relationship will be. maintained Vuntil they aretaken tainers. i s t Thelpunch retainer 6 is usually square'in shape, as shown in Figure 2. At two of its" Y ,corners it is provided with holes 7 for receiving dowel pins 8, while at its Vother two corners itis provided with holes 9 for receiving the threaded bolts 1l. n

Aitv he center of. the retainer is a'socket 12" for receiving the shank 13 of the punch 414:. This socket is `usually ofsuch size that the shank will have a running iit therewith.

The retaining plate is fastened to the pressure plate 16, which formspart ofthe ram,

(not shown)rby the threaded bolts 11. At a Y point adjacent the socket 12 and over-running intoV said socketis a circular recess 17 which has a vdrilled and tapped hole 18, eccentric with said recess, and is :for the purposeofa. receiving a bolt 19.

` liittingI around the and, at some arcuate positions, abutting the wall Vofthe recess 17 is aneccentric 21 whose edge is adapted'to enter a slot 22 in the punch Vshankli andl when so positioned the'eccen- .causes ytorn -work and oftentimes broken .punches and dies.

i out- `of their respective Arebodyof the bolt 19 Y Y tric will befapproximately concentric with the circular recess 17, as shown` in Figure2.

In inserting the punch intov the socket 12,

the slotted side thereofis` positioned .toward the center of the bolt 19 aroundwhich the eccentricA oscillates and the eccentric is then moved into the position shown inFigure 2 so that its edgewill enter the recess 22, binding the punch shank firmly against'the op-` I posite wall 28,Whereupon the-bolt191isfasltenedsecurely so as `tofbind the eccentric between the inner wallof the'recess 17and the bolt 19.

:The dieV is `:fastened in a retainer 26v f which is, in turn, fastened to the foundation plate 27 by means of the doWels 8 and bolts l1 in the manner explained in connection With the connection of the punch retainer to 5 the pressure plate.

The center of the retainer 26 has a socket 28 forV receiving the lower end of the die, Whichisfprovided With a hole.29 for receiving the punch 147 said hole tapering outward io towards its bott-Qm,.as sh0wn 2115.31, for the punched outl material to `drop'tliroug'h the same and through a hole 32 in thefoundation plate 27 to a suitable box or other means for catching the punched-voutportions This die 24 is also provided With a slot .-.ori groove '330r receiving'theedge of an eccentric 34 mounted to oscillate on a bolt .136 ina recess 37. laThe die 24 is pressed firmly Y v"by the eccentric-'34-against the opposite Wall .20 38,1said eccentric operates insthemanner described .as'to the cam` 21, Whichiholdsthe punch It is-.un'derstoodthat when thebolts 19 or fw.S6-are loosenedandthe eccentric 21 or 34 areoscillatedin'the direction of the arrows shewnithereonathat they will 4entirely clear ther groove,I 22v inthe punch: and the groove 33 in the die so that either the punch or the fdie ,maybemeadily WthdraWnJrom their l` :respective sockets :12. and 28.

With thisv formt of` :securing mechanism 1I t-havewfound thatthe lifeqof the punch vand -llieeisimaterially lengthened, and the lcut edges of the Workarealways sharp and clean iga-nd-injury to;eitherrthezpunch or` the die avoided.

fOfcourse, the punch and die locking mechanism illustrated may be changed in various `Nays iwithoutdeparting from the Vinvention 40 ihereinset fort-h and hereafter claimed.

The `invention ishereby claimed as follows: a

;1. A punch-press vtool-,retainer having a :toolcsocket anda circularrecess Within the ffaceof the retainer circumferentially overrunning the socket, a tool having `a groove nfits side andttngthe socket,a tension r,11.10113 :eccentrically positioned Within ythe recess, andan ,eccentric plate Wholly withinthe ofrecess and oscillating :upon i the bolt and ,adaptedltoswing to. engage Within the groove and to; Clampwthetool against; the Wall of the socket opposite.

2. LArpunchfpressftool-retainerhaving ax- 55 ially parallel a;t0,ol socket and overrunning :recessfextending in from its face, and a securing `member :mounted to oscillate infthe recess in a plane, parallel With the -i'aceo` the retainenandrhavingfa. cam surface :for making .linking Va-ndclampng engagement With aitool Withinthe socket.

In testimony whereof I )have signedmy :nameitoithisspeccation.

GLEMENS J. MARKSON. 

